A variety of skin rashes are knowned to occur as a part of the serum sickness-like prodrome of acute viral hepatitis which is thought to be due to immune complex deposition. We report the histologic and immunofluorescent findings in the skin and the seroloigc abnormalities in a patient with both erythematous maculopapular and purpuric rashes. We found circulating hepatitis B surface antigen (HBsAg), hypocomplementemia and cultaneous vasculitis associated with deposition of immunoglobulin and complement in the skin. We could not demonstrate intradermal deposition of HBsAg, but the findings are consistent with the immune complex hypothesis.